Several strains of Pseudomonas aeruginosa are cultured under aerobic and anaerobic conditions. Specific strains of P. aeruginosa which demonstrated the capability of producing nitric oxide are selected for further studies. Nitric oxide production is monitored by EPR-spin trapping technique. Sodium N-methyl-D-glucamine dithiocarbamate is the spin trap used. The role of nitric oxide reductase in nitric oxide production will be investigated. The impact of P. aeruginosa as a possible life-threatening pathogen will also be studied using animal models.